I've started a new thread as all my new questions are off-topic in my old thread.
So here I've been under the impression that RouterOS can only be installed via the serial port on the RouterBoard.
After Normis gave me a heads up, and after seeing this wiki, I'm very pleased one can do a simple "drag and drop" procedure. (ala Windows)
Now my actual question: What about the old RouterOS? What happens to it and do I need to format the NAND storage before installing a new RouterOS?
Or will it just be a RouterOS upgrade? Does this mean the new packages overwrite the old ones?